Telescopic sight with variable magnification

ABSTRACT

A telescopic sight with variable magnification includes an adjusting ring for varying the magnification. The telescopic sight housing and an eyepiece stub are arranged together in a single part. The adjusting ring is arranged between the eyepiece and an object in a groove formed between the telescopic sight housing and the eyepiece stub.

BACKGROUND OF THE INVENTION

The invention relates to a telescopic sight with variable magnification,more particularly, to a telescopic sight in which the magnification ischanged by means of an adjusting ring.

1. Discussion of Prior Art

Such telescopic sights with variable magnification are already known inthe state of the art.

A telescopic sight is known from U.S. Pat. No. 4,072,396 in which theadjusting ring is arranged on the objective lens. However, this positionof the adjusting ring is impractical in use. The same holds for thetelescopic sight which is known from U.S. Pat. No. 3,423,146.

A telescopic sight is known from U.S. Pat. No. 4,255,013 in which theadjusting ring projects beyond the telescopic sight housing on theeyepiece side. Also, in the telescopic sight which is known from U.S.3,948,587, the adjusting ring projects beyond its whole circumferenceout of the housing of the telescopic sight.

In the telescopic sights which are known from U.S. Pat. No. 3,782,822and U.S. Pat. No. 4,172,634, the adjusting ring is arranged on theeyepiece side, but here also projects from the housing of the telescopicsight over its full circumference.

2. Summary of the Invention

The invention has as its object to obtain a higher stability of thehousing together with a simplification of manufacture, with theadjustment taking place at a position which is convenient for use, andthe design making possible a substantially smooth surface.

This object is attained according to the invention by a telescopic sightwith variable magnification, in which the magnification is varied bymeans of an adjusting ring and the telescopic sight includes a housingand an eyepiece stub that together form a single part, the adjustingring is arranged between the eyepiece and the object, and a groove inwhich the adjusting ring is guided is formed between the telescopicsight housing and the eyepiece stub.

When the telescopic sight housing and the eyepiece stub are madetogether as a single part, according to the invention, not only is thereone part less to manufacture for the telescopic sight, but thissimplification of manufacture also has the advantage that the connectionbetween the two parts is solid, and a higher stability of the system isthus obtained.

In an advantageous manner, a groove is formed between the telescopicsight housing and the eyepiece stub, the adjusting ring being guided inthe groove. This feature aims at a more secure guiding of the adjustingring in relation to the direction of the optical axis.

In order to obtain a simple mounting procedure, the adjusting ring isarranged in an advantageous manner around the telescopic sight housing.

The mounting of the adjusting ring is effected in a very uncomplicatedmanner if the adjusting ring is constructed from two half shellsegments, which are connected together in the mounted state to form acircular body. Moreover this permits the materials used for theadjusting ring to be no longer restricted to only certain materials.

In particular, the use of light alloy or a hard plastic for the halfshells of the adjusting ring is advantageous.

A pin, projecting from a pin seating which is formed in the adjustingring, is fitted so that the magnification can be varied; the pin candrive the inner moving elements.

To secure the adjusting ring against inadvertent dismantling into itstwo component parts, an elastic auxiliary member is to be arrangedaround the adjusting ring.

The elastic auxiliary member is then advantageously made of rubber,which can in addition seal the opening in the telescopic sight housing.

In order to produce a good connection between the adjusting ring and theauxiliary member, recesses and/or raised portions are to be arranged inthe adjusting ring, and engage in corresponding raised portions and/orrecesses of the elastic auxiliary member.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to preferredembodiments, taken together with the drawings, in which:

FIG. 1 shows a section through a telescopic sight with the magnificationadjustment according to the invention;

FIG. 2a shows a vertical section through the upper half circle of theadjusting element;

FIG. 2b shows a side view of the upper half circle of the adjustingelement;

FIG. 3a shows a side view of the lower half circle of the adjustingelement;

FIG. 3b shows a side view of the lower half circle of the adjustingelement;

FIG. 4 shows a side view of the outer casing of the telescopic sight inthe region of the magnification adjustment according to the invention;

FIG. 5a shows a section through the outer rubber cover; and

FIG. 5b shows a detail of a view of the outer rubber cover.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a section through the telescopic sight (1) with variablemagnification, according to the invention, in the region where theeyepiece stub joins the telescopic sight housing. The telescopic sighthousing and the eyepiece stub are made in one piece (2).

A groove (3) is present between the eyepiece stub and the remainder ofthe telescopic sight housing, and provides a guide for the adjustingring (4). An elastic auxiliary member (5) of rubber is arranged aroundthe adjusting ring (4); it is slipped over the adjusting ring (4) afterthis has been mounted.

A pin seating (4a), into which a pin (6) projects, is present in theadjusting ring (4). This pin (6) transmits the radial motion of theadjusting ring (4) to an inner hollow cylinder (7), which causes therequired lens movements. A pin (8) is also present on the opposite sideof the telescopic sight housing (2), and provides a counteracting forceto the adjusting pin (6).

The adjusting ring (4) together with the auxiliary member (5) does notproject beyond the upper edge of the groove (3).

In FIGS. 2a and 2b, and also in FIGS. 3a and 3b, the half shell segments(4.1, 4.2) of the adjusting ring are shown.

The upper half shell (4.1) is a circular annular body and has asemicircular cross section which is greater than 180°. A convexity(4.1a) is present in the upper portion of this half shell (4.1), and hasan aperture (4a), directed inward, which serves as a pin seating. Thehalf shell (4.1) has respective rectangular apertures (4.1b, 4.1c) oneach side of this convexity (4.1a).

Two T-shaped apertures (4.1d, 4.1e) are formed at the ends of the upperhalf shell (4.1).

The lower half shell (4.2) is also a semicircular body and also has asemicircular cross section, which is greater than 180°. It has tworectangular apertures (4.2b, 4.2c) at the sides of its lowest point(4.2a).

Two T-shaped extensions (4.2d, 4.2e) are present at the ends of thelower half shell (4.2), and fit exactly into the T-shaped openings(4.1d, 4.1e) of the upper half shell (4.1).

If the two half shells (4.1, 4.2) of plastic are fitted together, thetwo T-shaped extensions (4.2d, 4.2e) engage in the two T-shaped openings(4.1d, 4.1e), and the two half shells (4.1, 4.2) form a closed circlewithout play.

If the adjusting ring (4), with its two half shells (4.1, 4.2), ismounted in the groove (3) of the telescopic sight housing (2), theelastic auxiliary member, shown in cross section in FIG. 5a, is slippedover the adjusting ring (4) so that its recess (5a) and its raisedportions (5b-5e) engage exactly on the convexity (4.1a) or in therectangular apertures (4.1b, 4.1c, 4.2b, 4.2c) of the adjusting ring(4). For indication of the setting of the adjusting ring (4),corresponding markings are present on the auxiliary member (5), in theform of numerals and dots as shown in FIG. 5b.

What is claimed is:
 1. A telescopic sight (1) with variablemagnification, comprising:a telescopic sight housing (2) and an eyepiecestub arranged together as a single part, and an adjusting ring (4)arranged between an eyepiece and an object, wherein a groove for guidingsaid adjusting ring is arranged between said telescopic sight housing(2) and said eyepiece stub and wherein said adjusting ring (4) does notproject beyond an upper edge of said groove.
 2. The telescopic sightaccording to claim 1, in which said adjusting ring (4) is arrangedaround said telescopic sight housing (2).
 3. The telescopic sightaccording to claim 1, wherein said adjusting ring (4) comprises two halfshells (4.1, 4.2) connected together to form a circular body, in amounted state.
 4. The telescopic sight according to claim 3, whereinsaid two half shells (4.1, 4.2) are made of a light alloy or hardplastic.
 5. The telescopic sight according to claim 1, furthercomprising a pin seating (4a) formed in said adjusting ring and a pin(6) arranged in said pin seating (4a) and projecting inward for drivinginternal moving elements of said telescopic sight.
 6. The telescopicsight according to claim 1, further comprising an elastic auxiliarymember (5) arranged around said adjusting ring (4).
 7. The telescopicsight according to claim 6, wherein said elastic auxiliary member (5) ismade of rubber.
 8. The telescopic sight according to claim 6, whereinsaid adjusting ring (4) includes recesses or raised portions and saidelastic auxiliary member (5) includes corresponding raised portions orrecesses for engaging in said recesses or raised portions of saidadjusting ring (4).